Related papers: Interferometric Observations of the Hierarchical T…
We reported a cyclic variation of $O-C$ diagram with a semi-amplitude of 0.0033 days and a period of 1.05 years for the pulsating eclipsing binary HZ Dra. The cyclic variation can be explained by the light travel-time effect via the…
We report a comprehensive search for hierarchical triple stellar system candidates amongst eclipsing binaries (EB) observed by the CoRoT spacecraft. We calculate and check eclipse timing variation (ETV) diagrams for almost 1500 EBs in an…
The analysis of spectroscopic data for 30 Algol-type binaries is presented. All these systems are short period Algols having primaries with spectral types B and A. Dominant spectral lines were identified for the spectra collected and their…
A growing number of close binary stars are being discovered among central stars of planetary nebulae. Recent and ongoing surveys are finding new systems and contributing to our knowledge of the evolution of close binary systems. The push to…
The existence of an additional body around a binary system can be detected by the help of the light-travel time effect. Due to the motions of binary and the companion stars around the common mass center of the ternary system, the light-time…
We searched the orbital period changes in 182 EA-type (including the 101 Algol systems used by \cite{hal89}), 43 EB-type and 53 EW-type binaries with known both the mass ratio and the spectral type of their secondary components. We…
The results of speckle interferometric observations at the 4.1 m Southern Astrophysical Research Telescope (SOAR) in 2019 are given, totaling 2555 measurements of 1972 resolved pairs with separations from 15 mas (median 0.21") and magnitude…
Three Algol-type binary systems (IO Cep, IM Cep and TX Ari) showing cyclic orbital period changes are studied. The combination of time of minimum data from the ground-based observations together with high precision photometric data from the…
We have measured the angular diameters of six M dwarfs with the CHARA Array, a long-baseline optical interferometer located at Mount Wilson Observatory. Spectral types range from M1.0 V to M3.0 V and linear radii from 0.38 to 0.69 Rsun.…
We present results of the CFHT adaptive optics search for companions of a homogeneous group of contact binary stars, as a contribution to our attempts to prove a hypothesis that these binaries require a third star to become so close as…
CCD light curves of the Algol type eclipsing binaries DP Cep, AL Gem, FG Gem, UU Leo, CF Tau and AW Vul were analysed using the Wilson-Deninney code and new geometric and absolute parameters were derived. Due to cyclic apparent orbital…
This paper presents a new algorithm, TRIMOR, to analyse multi-order spectra of triple systems. The algorithm is an extension of TRICOR, the three-dimensional correlation technique that derives the radial velocities of triple stellar systems…
The results of speckle interferometric observations at the 4.1 m SOAR telescope in 2016 and 2017 are given, totaling 2483 measurements of 1570 resolved pairs and 609 non-resolutions. We describe briefly recent changes in the instrument and…
The results of speckle interferometric observations at the 4.1 m Southern Astrophysical Research Telescope (SOAR) in 2018 are given, totaling 3097 measurements of 2427 resolved pairs with separations from 11 mas to 5.9" (median 0.15",…
HD 100453AB is a 10+/-2 Myr old binary whose protoplanetary disk was recently revealed to host a global two-armed spiral structure. Given the relatively small projected separation of the binary (1.05", or ~108 au), gravitational…
V455 Car is a southern oscillating eclipsing Algol-type system with an orbital period of 5.132888 days. Our first photometric solutions based on the Transiting Exoplanet Survey Satellite indicate that it is a semi-detached binary with the…
Light curves of the long-period Algols are known for their complex shape (asymmetry in the eclipse, light variations outside eclipse, changes from cycle-to-cycle), and their interpretation is not possible in the standard model of binary…
The systems V819 Her, V2388 Oph, and V1031 Ori are triples comprised of an eclipsing binary orbiting with a distant visual component on a longer orbit. A detailed analysis of these interesting systems, combining the two observational…
Delta Cir is known as an O7.5 III eclipsing and spectroscopic binary with an eccentric orbit. Penny et al. discovered the presence of a third component in the IUE spectra. The eclipsing binary and the third body revolve around a common…
The discovery and characterization of Algol eclipsing binaries (EAs) provide an opportunity to contribute for a better picture of the structure and evolution of low-mass stars. However, the cadence of most current photometric surveys…